Several recent studies show that immigrants exhibit higher levels of trust in public institutions than natives. This study uses pooled data from the European Social Survey to examine possible reasons for this ‘over-confidence’ of immigrants, arguing that it is largely the relatively lower expectations of immigrants from countries with poorer institutional performance that account for this difference. The eminent role of expectations is also underscored by the finding that low social standing matters less for the level of trust of immigrants than it does for natives. The ‘frame of reference effect’ weakens over time and with increased acculturation in the country of residence, suggesting that expectations are less strongly based on experienc...